-LRB- CNN -RRB- -- A federal judge in New Orleans ruled Thursday that Transocean is not liable for Deepwater Horizon compensatory damages sought by third parties in the worst oil spill in U.S. history .

There are more than 120,000 plaintiffs in the lawsuit , scheduled to go to trial on February 27 in New Orleans . Third parties comprise the vast majority of plaintiffs .

Transocean owned the Deepwater Horizon rig that exploded on April 20 , 2010 , killing 11 people .

Transocean is still potentially liable for punitive damages or civil penalties under the Clean Water Act .

A spokesman for Transocean said the ruling confirms `` that BP is responsible for all economic damages caused by the oil that leaked from its Macondo well , and discredits BP 's ongoing attempts to evade both its contractual and financial obligations .

`` Transocean is pleased to see its position affirmed , consistent with the law and the long-established model for allocating risks in the offshore-oil and gas industry , '' spokesman Lou Colasuonno said .

BP , the oil company that contracted the rig , highlighted liabilities Transocean still potentially faces .

`` Under the decision Transocean is , at a minimum , financially responsible for any punitive damages , fines and penalties flowing from its own conduct . As we have said from the beginning , Transocean can not avoid its responsibility for this accident , '' a BP statement said .

`` By contrast , since the spill we have stepped up , acknowledged our role and paid more than $ 7.8 billion in claims , advances and other payments to individuals , businesses and governments , '' BP said .

`` Today 's ruling makes clear that contractors will be held accountable for their actions under the law . While all official investigations have concluded that Transocean played a causal role in the accident , the contractor has long contended it is fully indemnified by BP for the liabilities resulting from the oil spill . The court rejected this view , '' BP said .

CNN 's Michael Martinez contributed to this report .

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Federal judge says Transocean is n't liable for third parties ' compensatory damages

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Those third parties comprise the vast majority of plaintiffs

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The Deepwater Horizon explosion caused the worst oil spill in U.S. history

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The lawsuit will go to trial February 27 in New Orleans